Guy Stagg blogs about literature, the relationship between culture and politics and, when all else fails, the zeitgeist.

Too much Moriarty: less is more when it comes to Sherlock Holmes's arch-enemy

Sherlock Holmes has been portrayed on film more times than any other fictional character. But Professor Moriarty must be coming in a close second. As Guy Ritchie’s latest effort shows, Holmes taking on Moriarty has almost as much box office draw as Alien vs Predator.

These days just about every outing for the great detective will feature Moriarty as well, whether Sherlock, the BBC’s 21st-century reboot of the franchise, or Anthony Horowitz’s new Holmes novel The House of Silk. Indeed, those who have not read the original mysteries could be forgiven for thinking that Holmes only leaves 221B Baker Street to do battle with his arch-nemesis.

Arthur Conan Doyle created a rich and varied cast of villains. But Moriarty only turns up in the books twice. Once in the The Valley of Fear, where the Napoleon of Crime’s malevolent presence is detected by Holmes, but never materialises. And more famously in The Final Problem, where Moriarty was invented to provide a fitting opponent in Holmes' last case.

Even so, there is not much substance to him. Holmes makes a lot of fuss about the Moriarty’s "phenomenal mental capacity", but when Watson finally sees the Professor, the only description we get is of a tall man in an overcoat and top hat – like every other gentleman in Victorian London. What is more, despite the fact that the evil genius is behind half the crimes committed in Britain, in the actual narrative he is responsible for little more than a few bungled attempts on Holmes’ life.

In total, Professor Moriarty's presence in the Holmes canon must amount to about twenty pages. Conan Doyle probably gives him about as much attention as Watson’s wife.

It is possible to see this as a creative failure: having built up the baddie, Conan Doyle felt he was unable to deliver. But in fact the opposite is true. Conan Doyle knew exactly what he was doing, and knew that the less he gave us, the more our imaginations would fill in. That is what makes Professor Moriarty so vivid.

The same is true of Kurtz, the other great villain of late-Victorian literature. Kurtz is the demonic ivory trader in Joseph Conrad's Heart of Darkness. He only appears in the last quarter of the book, and even then Conrad is far from generous. All we get is a dying man with a head like a skull, some incoherent ramblings about power, and a voice – that voice. Yet out of these fragments Conrad creates one of the most powerful and enduring figures in fiction.

It is the very anticlimax of Kurtz that makes him so memorable. Like Moriarty, the smaller the role, the bigger we imagine them. But films seem to miss this fact. And so they fit Moriarty into the script however they can, and then cast underwhelming actors to the play the part. Few directors appreciate the fact the more you see of the man, the less compelling he becomes. Moriarty is a mystery – and we should keep him that way.